On 17 and 18 October, the System Architecture Review (briefly, SAR) of the ESO/ELT ANDES (ArmazoNes high Dispersion Echelle Spectrograph) instrument took place at the ESO headquarters in Garching. ANDES (https://andes.inaf.it) is one of the instruments for the future 39m optical-infrared telescope, the ELT (Extremely Large Telescope - https://elt.eso.org), currently under construction on the Cerro Armazones mountain, in the Atacama Desert in Chile. It is a spectrograph with high resolution, extreme precision and stability, capable of covering, with a single observation, a range in wavelengths from U (0.35nm) to K (2.4 µm).
The construction of ANDES is entrusted to an international consortium made up of over 230 researchers and technologists from 24 institutes/universities distributed in 13 countries under the guidance of INAF (PI: Alessandro Marconi, PM: Paolo Di Marcantonio) and which also sees a large participation of the Trieste Observatory staff with both scientific and technological interests.
The instrument aims to answer some fundamental questions of current astronomical scientific research such as the existence of life on planets outside our solar system (exoplanets), how our universe was born, how it is evolving, how the first stars and galaxies formed.
The steel skeleton of the ELT telescope dome (under construction) illuminated by the light of the full moon; the height of the dome exceeds 80m (Courtesy ESO)
The SAR is the first milestone in the construction phase of ANDES (which is expected to last 10 years) and precedes the Preliminary Design Review. The review, which was passed successfully, certified the validity of the adopted architecture for ANDES which foresees an instrument composed of four spectrographs, all thermally stabilized, placed in a pressure-stabilized vacuum vessel (to guarantee extreme stability) , having dimensions larger than any similar spectrograph built to date. The various spectrographs are fed by fibers that bring the light of the astronomical object under observation into the spectrographs where it is split into individual wavelengths. ANDES is also equipped with an adaptive optics module capable of correcting and substantially canceling the effects of atmospheric turbulence and a cutting-edge calibration system to guarantee the necessary precision and accuracy required for the analysis of the obtained spectra.
ANDES architecture with the four spectrographs and their respective wavelength coverage
Artistic vision of the distributions of the various ANDES modules at ELT
